Park staff and WildlifeDirect officials stationed in Virunga's Bukima camp said they heard gunshots coming from inside the dense forest around 8 p.m. on Sunday.

When the rangers ventured into the forest on Monday morning, they found the three female gorillas.

"The gorillas were all quite close together. They had all been shot," de Merode said.

In addition to Safari, another dead female was the mother of a two-year-old. The third gorilla killed was pregnant.

It was not until the following day that rangers found the silverback Senkekwe, the leader of the so-called Rugendo family of 12 individuals.

Another two gorillas from the family are reportedly missing, their fate unknown.

Rebel Militias

The Rugendo family is one of several groups of gorillas that live on the Congo side of the sprawling Virunga National Park, which straddles the border of Congo, Rwanda, and Uganda, and are visited from the Bukima camp (see Africa map).

More than half of the gorillas' population, estimated at about 700, is found in Virunga. The rest live in forests in Rwanda and Uganda.

The park lies in the heart of one of the most troubled regions of Africa.

The Democratic Republic of Congo is struggling to emerge from a civil war that has left an estimated four million people dead and dates back to the genocide in Rwanda in 1994.

Today the area is home to a vast array of rebel militias, government soldiers, foreign troops, and villagers who are unsympathetic to the rangers protecting the park. Poaching remains a major problem.